National Repository of Grey Literature 2 records found  Search took 0.09 seconds. 
Determination of complexation constants of weak electrolyte analytes by Affinity capillary electrophroesis
Ansorge, Martin ; Šteflová, Jana (advisor) ; Ušelová, Kateřina (referee)
Capillary electrophoresis is not only excellent separation technique but it is often advantageously used for determination of physical-chemical parameters of compounds such as complexation constants of analyte and appropriate complexation agent. The most frequently used electrophoretic method for determination of complexation constants is affinity capillary electrophoresis. In the frame of this work the affinity capillary electrophoresis is used for determination of complexation constants of R and S enantiomers of flurbiprofen, particularly both its neutral and fully dissociated form with neutral β- cyclodextrin. For this purpose we utilized classical method introduced in literature, where complexation constants are determined at two pHs, where analyte is fully and partially dissociated, respectively. Simultaneously, the complexation constants were observed by the new method based on multidimensional nonlinear regression, where all data measured at different pHs and β-cyclodextrin concentrations were utilized for evaluation. Results show that classical method can be highly confusing, especially if unsuitable pH is chosen for determination of stability constants of neutral form of analyte. Multidimensional regression method provides substantially more reliable data but with higher error of estimate....
Determination of complexation constants of weak electrolyte analytes by Affinity capillary electrophroesis
Ansorge, Martin ; Šteflová, Jana (advisor) ; Ušelová, Kateřina (referee)
Capillary electrophoresis is not only excellent separation technique but it is often advantageously used for determination of physical-chemical parameters of compounds such as complexation constants of analyte and appropriate complexation agent. The most frequently used electrophoretic method for determination of complexation constants is affinity capillary electrophoresis. In the frame of this work the affinity capillary electrophoresis is used for determination of complexation constants of R and S enantiomers of flurbiprofen, particularly both its neutral and fully dissociated form with neutral β- cyclodextrin. For this purpose we utilized classical method introduced in literature, where complexation constants are determined at two pHs, where analyte is fully and partially dissociated, respectively. Simultaneously, the complexation constants were observed by the new method based on multidimensional nonlinear regression, where all data measured at different pHs and β-cyclodextrin concentrations were utilized for evaluation. Results show that classical method can be highly confusing, especially if unsuitable pH is chosen for determination of stability constants of neutral form of analyte. Multidimensional regression method provides substantially more reliable data but with higher error of estimate....

Interested in being notified about new results for this query?
Subscribe to the RSS feed.